A review of the impact of outdoor and indoor environmental factors on human health in China

Environmental Science and Pollution Research - The Intergovernmental Panel on Climate Change (IPCC) reported that global climate change has led to the increased occurrence of extreme weather...     

Removal of gentian violet and rhodamine B using banyan aerial roots after modification and mechanism studies of differential adsorption behaviors

Environmental Science and Pollution Research - A novel adsorbent derived from banyan aerial roots was prepared via modification and employed to aqueous gentian violet (GV) and rhodamine B (RhB)...     

Species identification and mutation breeding of silicon-activating bacteria isolated from electrolytic manganese residue

Environmental Science and Pollution Research - A strain of silicon-activating bacteria was isolated from electrolytic manganese residue (EMR); identified as a species of Ochrobactrum by integrated...     

典型农业活动区土壤重金属污染特征及生态风险评价

联合野外采样和室内分析,以典型农田土壤为研究对象,分析土壤中重金属Cr、Ni、Cu、Zn、Cd、Pb、As和Hg的含量及污染特征,并采用单因子污染指数法、内梅罗污染指数法及潜在生态危害指数法,对农田土壤进行生态风险评价,同时利用主成分因子分析法,提取出3主因子,分析土壤重金属可能来源。结果表明,研究区农田土壤各重金属含量均高于背景值,表层污染程度高于底层;各重金属单因子污染指数对应污染等级均为清洁,内梅罗污染指数为0.46,污染等级为安全。潜在生态风险评估结果显示,研究区土壤重金属污染的潜在生态风险危害程度为中等,各重金属的潜在生态危害程度依次为Cd> Hg> As> Cu> Pb> Ni> Cr> Zn。主成分因子分析显示,研究区土壤中Hg、As和Cr主要由工业污染源贡献,土壤中Cd、Pb的污染主要来源于不合理的农业生产活动和居民生活,Ni、Zn和Cu与自然成土过程密切相关。综合评价表明,尽管研究区农田土壤目前重金属污染情况较轻,未达到警戒水平,但由于城市化的发展及长期现代化农业耕作活动造成农田土壤重金属的富集,因此,增强农田土壤安全性生产管理、严控土壤污染源与推行标准农业生产是十分必要的。     

聚乙烯醇(PVA)改性膨胀石墨对亚甲基蓝废水的吸附

以天然鳞片石墨为原料,聚乙烯醇 (PVA) 为改性剂,采用浸渍法制备改性膨胀石墨 (M-EG), 对改性膨胀石墨 (M-EG) 的官能团结构组成、比表面积、孔径分布及孔隙度等进行了表征,研究了其对亚甲基蓝染料废水的吸附性能,并对其吸附动力学、等温吸附类型和吸附热力学进行了研究.结果表明,经PVA改性后,M-EG的比表面积、孔隙度均增大,表面极性降低;M-EG对亚甲基蓝染料的吸附符合二级动力学吸附模型,并符合Langmiur等温吸附模型和Freundlich等温吸附模型;该反应为吸热的自发反应.     

多种神经网络在华北西部区域城市空气质量预测中的应用

据华北西部区域4个主要城市2003—2012年API日报数据和相应时段的地面气象要素数据,利用4种(BP、Elman、T-S模糊、小波)神经网络构建预测模型并预测相应城市大气环境质量.研究结果显示,4种模型在可靠性、预测精度方面均可满足应用要求可用于实际预测;具有动态反馈能力的Elman神经网络的预测精度以及泛用性要优于具静态馈能力的其他3种网络模型,说明动态神经网络更适用于城市大气环境质量预测.4种神经网络的决策权重大小及其排序虽各不相同,但体现出相似规律性,日最低气温、日均气压、前日API对输出数据的影响较大,说明逆温现象引发的持续性、区域性污染是该地区主要环境问题.     

不同泥质类型河流底泥脱水药剂优化实验研究

为了考察几种典型脱水絮凝剂对各泥质类型底泥脱水性能的影响,对3条不同泥质类型的典型河流(沙质、泥沙混合质、泥质)底泥的脱水效果进行了研究.结果表明,在一定投加量范围内,所有脱水药剂均能不同程度改善各泥质类型底泥的脱水性能.无机絮凝剂建议选择PAFC(聚合氯化铝铁)或PAC(聚合氯化铝),其中PAFC的最佳投加范围为0.4%~1.6%,PAC的最佳投加范围为0.4%~2.0%;有机高分子絮凝剂建议选择CPAM(阳离子聚丙烯酰胺),最佳投加范围为0.01%~0.03%;在各絮凝剂最优投加条件下,泥质底泥的脱水性能提高最为明显,其比阻最大可下降86%,泥沙混合质底泥污泥比阻最大可下降81%,沙质底泥污泥比阻则最大可下降58%.而当复合混凝剂为PAC和CPAM或PAFC和CPAM时,沙质底泥在优化混凝条件下其污泥比阻最大可分别下降82%和76%.     

Management of hazardous fly-ash energy waste in the adsorptive removal of diclofenac by the use of synthetic zeolitic materials

Zeolite-carbon composites (Na-P1(C), Na-X(C)) and pure zeolites (Na-P1, Na-X) were synthesized from hazardous high-carbon fly ash waste (HC FA) via hydrothermal reaction with sodium hydroxide (NaOH). These solids were applied in the removal of diclofenac (DCF) from aqueous solution, with and without poly(acrylic acid) (PAA). The experiments included adsorption–desorption measurements, as well as electrokinetic and stability analyses. The obtained results showed that HC FA and Na-P1(C) had the greatest adsorption capacity towards DCF, i.e., 26.51 and 21.19 mg/g, respectively. PAA caused considerable decrease in the DCF adsorption due to the competition of both adsorbates of anionic character for active sites. For example, the adsorbed amount of DCF on Na-P1 without PAA was 14.11 mg/g, whereas the one measured with PAA was 5.08 mg/g. Most of prepared solids were effectively regenerated by the use of NaOH. Desorption degree reached even 73.65% in the single systems (with one adsorbate) and 97.24% in the mixed ones (with two adsorbates). Zeolitic materials formed suspensions of rather low stability, which underwent further deterioration in the organic molecules presence. All the results obtained in this study indicated that HC FA can be successfully managed in the removal of organic substances.

     

垂直厌氧折流板反应器处理树脂废水的中试研究

介绍了采用垂直厌氧折流板反应器(VABR)处理离子交换树脂生产废水的中试实验装置以及实验研究过程,并着重分析了COD容积负荷和盐分对COD的去除率及出水VFA的影响,并确定了该废水的厌氧产沼气率。研究结果表明,在中温(37±1℃)环境下,容积负荷在9 kg COD/(m3.d)左右时,HRT为24 h的条件下,VABR对COD的平均去除率保持在70%左右,平均每去除1 kg COD约产生沼气0.44 m3,且运行稳定。     

几种阴阳离子对磷钨酸光催化降解甲基橙的影响

以磷钨酸为光催化剂,在紫外灯照射下,对甲基橙溶液进行光催化降解,考察了几种阴阳离子对磷钨酸光催化降解甲基橙溶液的影响。结果表明：Mg²⁺、Ca²⁺、NO^-₃、SO^2-₄和CO^2-₃均对催化活性有促进作用,其中Mg²⁺和Ca²⁺仅有微弱的促进作用;NO^-₃和SO^2-₄随着浓度的增加促进作用也有所增加;CO^2-₃则随着浓度的增加促进作用呈下降趋势;Mn²⁺、Al³⁺和Cl^-对光解反应存在较强的抑制作用,且Al³⁺和Cl^-随着其浓度的增加,抑制作用增强。